This blog provides some broad suggestions for determining which planetary mixer arrangement is best for a given application.
For viscous and dense applications, double planetary mixers and planetary dispersers are typically utilized. While encircling the vessel, the agitators revolve on their own axes. Regardless of product rheology, this results in a very thorough mixing action. Until a homogeneous condition is established, batch components are repeatedly recombined and transported from one section of the vessel to another.
Planetary mixers are also used for granulation and vacuum drying, in addition to their principal usage in combining high viscosity compositions. Here are some tips to assist you to choose the optimal planetary mixer setup for your process if you’re in the market for one.
What is your application’s viscosity range?
The viscosity of most batch mixing operations will change several times. Consider the viscosity of your starting liquids, the maximum viscosity obtained during mixing, and the final viscosity after letting down or incorporating all raw components. Double planetary mixers can handle a larger range of viscosities than planetary dispersers. A twin planetary mixer with helical stirrers, such as Ross High Viscosity “HV” blades (US Patent No. 6,652,137), can mix materials up to 6 million cP or higher.
Do you require agitation at a high rate?
This problem is also related to viscosity. Double planetary mixers work at modest speeds, relying on the high viscosity of the product to impart shear and disintegrate any agglomerates in the batch. When working with materials with a pressure range of 100,000 to 2 million cP, a planetary disperser’s high-speed mixing action is more successful at wetting out solids and providing a fine dispersion. Two planetary stirrers and two disperser shafts help with some very difficult applications. These agitators’ combined mixing power is perfect for quickly incorporating large amounts of particles into a viscous vehicle. The most efficient method of processing and order of ingredient addition will be confirmed by mixer testing.
Certain materials will tend to rise up the vertical flights of the rectangular stirrer(s) and out of the mixing vessel, whether in a double planetary mixer or a planetary disperser. This type of batch material migration lowers mixing efficiency, involves extensive clean-up, and even increases contamination concerns. If you’re having problems with your material, try using “HV” blades instead. The sweeping arc of each helical leg of the HV blade follows a precisely inclined contour, forcefully pushing the product forward and downward and maintaining it within the mixing zone at all times.
Streamline your discharge procedure
Gravity alone takes a long time to discharge a viscous batch, and if the product is very thick or sticky, additional hours of human scraping may be required. Use an automated discharge system with your planetary mixer to make discharge and cleanup easier. The mixing vessel is wheeled to the discharge station and a platen is lowered into it in most setups. The platen has a custom-fitted O-ring that rides against the vessel wall, effectively wiping it clean. The finished product is driven out of the jar or platen by a valve.
So, these were the tips for selecting the best planetary mixer for your process. Promas Engineers is the best planetary mixer manufacturer, for more information on the planetary mixer machine, contact us.